FEMA 2002: WTC 7 fire-induced progressive collapse; further study needed

Observation

An early official engineering team attributed WTC 7 to fire while flagging that the mechanism was not fully understood.

Interpretation

Supports H005 as a working hypothesis in 2002, with documented incompleteness. Not an explosives finding.

Source text

FEMA/ASCE BPAT (2002) offered a fire-induced progressive-collapse hypothesis for WTC 7 while stating that the collapse was not understood in detail and that more research was required. NIST's later NCSTAR 1A is that further research.

Alternative investigators emphasise FEMA's uncertainty as evidence the fire story was incomplete, not as a demolition finding.

Hypothesis linkage

• H005supportsseeded

  FEMA 2002 fire-induced working hypothesis.